4.85 VOLT ULTRA LOW DROPOUT ZLDO485 REGULATOR ISSUE 2 - MAY 1997 DEVICE DESCRIPTION FEATURES The ZLDO Series low dropout linear Very low dropout voltage regulators operate with an exceptionally 6mV dropout at 10mA output low dropout voltage, typically only 30mV 30mV dropout at 100mA output with a load current of 100mA. The regulator series features output voltages in the range 100mV dropout at 300mA output 2.7 to 18 volts, this device provides an output 4.85 volt fixed output voltage of 4.85 volts. Other voltages available The ZLDO485 consumes a typical quiescent Low quiescent current current of only 1mA and is rated to supply 1mA quiescent (typ) at 300mA output load currents up to 300mA. A battery low flag is available to indicate potential power fail Low battery flag situations. If the input voltage falls to within Shutdown control 200mV of the regulated output voltage then Surface mount package the error output pulls low. The device also features an active high disable control. Once disabled the ZLDO quiescent current falls to typically 11A. APPLICATIONS The ZLDO devices are packaged in Zetex Battery powered devices SM8 8 pin small outline surface mount Portable instruments package, ideal for applications where space Portable communications saving is important. The device low dropout voltage, low quiescent current and small size Laptop/Palmtop computers make it ideal for low power and battery Electronic organisers powered applications. Battery powered circuits can make particular use of the low battery flag and shutdown features. Low Battery Flag Vin LOW BATTERY COMPARATOR THERMAL SHUTDOWN Vo OUTPUT DRIVE BIAS Shutdown Control CIRCUIT Cs SHUTDOWN BANDGAP REFERENCE Shaping Gnd 4-71ZLDO485 ABSOLUTE MAXIMUM RATING Input Supply Output Current 300mA Voltage Range -0.3 to 20V Operating Temperature -40 to 85C Shutdown Input Storage Temperature -55 to 150C Voltage Range -0.3 to V in Power Dissipation Low Battery Output (Tamb=25C) 2W (Note 1) Voltage Range -0.3 to 20V ELECTRICAL CHARACTERISTICS TEST CONDITIONS (Unless otherwise stated) T =25C,I =10mA,C =10pF,C =1F amb L s out Parameter SYMBOL CONDITIONS MIN. TYP. MAX. UNITS Output voltage V V =5.85V 4.75 4.85 4.95 V o in Output voltage V V =5.85V 100 250 ppm/C o in temperature coefficient (Note 2, Note 4) T Line regulation V =5.85 to 20V 20 69 mV/V V o in Load regulation V I =10 to 300mA 68 119 mV o L V =5.85V in Dropout voltage V -V I =10mA 6 10 mV in o L (Note3) I =100mA 30 75 L I =300mA 100 200 L Quiescent current I V =5.85V, I =0 0.63 1 mA q in L Quiescent current I V =5.85V, I =0, 11 30 A qs in L at shutdown V =V shdn in Shutdown control input I V =V =5.85V 2 10 A ins shdn in current Shutdown control V V =5.85V ts in threshold voltage low(on) 0.4 V high(off) 1.5 Output current in I V =20V 50 100 nA Ls in shutdown mode V =Gnd o (Note4) Output noise voltage e V =5.85V 190 V RMS n in (Note4) f=10Hz to100kHz, I =100mA L Low battery detect V V + Vo + V in(bld) o voltage 0.2V 0.4V Low battery flag V I =100A, 0.16 0.4 V bl bl output voltage V <V +200mV in o Low battery flag I V =6V, 0.1 1 A bl bl leakage current V >V +400mV in o 4-72